Ocean acidification: why soils play an important role

A new research is focusing on the role of soils in ocean acidification

by Lorenzo Ciotti
Ocean acidification: why soils play an important role

The process of continuous acidification of ocean waters undoubtedly leads to effects on the food chain and, in particular, can affect the lysocline and the compensation depth of the carbonates; resulting in the dissolution of the calcareous shells of shells, molluscs and calcareous plankton, made up of calcium carbonate.

The oceans in particular are able to absorb CO2 from the atmosphere and in doing so become acidified. When CO2 is dissolved to produce aqueous CO2, carbonic acid is also formed which will dissociate rapidly thus producing bicarbonate ions which in turn can dissociate into carbonate ion.

these reactions are able to produce protons thus lowering the pH value of the solution. A new research is focusing on the role of soils in ocean acidification. This is the study The role of soils in the regulation of ocean acidification, published on the Philosophical transactions of the Royal Society of London.

Series B, Biological sciences. The researchers said: "Soils play an important role in mediating chemical weathering reactions and carbon transfer from the land to the ocean. Proposals to increase the contribution of alkalinity to the oceans through 'enhanced weathering' as a means to help prevent climate change are gaining increasing attention.

This would augment the existing connection between the biogeochemical function of soils and alkalinity levels in the ocean. The feasibility of enhanced weathering depends on the combined influence of what minerals are added to soils, the formation of secondary minerals in soils and the drainage regime, and the partial pressure of respired CO2 around the dissolving mineral.

Increasing the alkalinity levels in the ocean through enhanced weathering could help to ameliorate the effects of ocean acidification in two ways. First, enhanced weathering would slightly elevate the pH of drainage waters, and the receiving coastal waters.

The elevated pH would result in an increase in carbonate mineral saturation states, and a partial reversal in the effects of elevated CO2. Second, the increase in alkalinity would help to replenish the ocean's buffering capacity by maintaining the Revelle Factor, making the oceans more resilient to further CO2 emissions.

However, there is limited research on the downstream and oceanic impacts of enhanced weathering on which to base deployment decisions."